Patent Application
20190195453
The present disclosure relates to lighting fixtures for vehicles and buildings, and, in particular, to a vehicle headlamp.
In the related art, a vehicle lamp creates a low-beam light distribution pattern and a high-beam light distribution pattern by reflecting light from two light sources by a reflector and a light emitting unit, respectively, and passing the light through a projection lens.
For example, in Japanese Patent Unexamined Publication No. 2016-39110, a low-beam light distribution pattern and a high-beam light distribution pattern are created as shown in
There is provided a vehicle headlamp capable of performing irradiation by switching low beam irradiation and high beam irradiation.
The vehicle headlamp includes a projection lens, a first lens, a second lens, a first light source, and a second light source.
The first lens and the second lens are disposed behind the projection lens.
The first light source is disposed behind the first lens.
The second light source is disposed behind the second lens.
The first lens and the second lens are disposed so as to deviate from an optical axis of the projection lens and to be opposite to each other.
The first lens includes a first irradiation port, a first entrance surface, a second entrance surface, a first reflection surface, and a second reflection surface.
The first irradiation port is opposite to an entrance surface of the projection lens.
The first entrance surface is opposite to the first light source and guides the light from the first light source to the first irradiation port.
The second entrance surface is disposed adjacent to the first entrance surface and guides the light failed to pass through the first entrance surface in a direction toward a sidewall of the first lens.
The first reflection surface reflects light entering from the second entrance surface and guides the light to the first irradiation port.
The second reflection surface reflects light passed through the first entrance surface and deflected from a direction toward the first irradiation port and light reflected from the first reflection surface and deflected from the direction toward the first irradiation port, and guides the light to the first irradiation port.
The second lens includes a second irradiation port, a third entrance surface, a fourth entrance surface, a third reflection surface, and a fourth reflection surface.
The second irradiation port is opposite to the entrance surface of the projection lens.
The third entrance surface is opposite to the second light source and guides light from the second light source to the second irradiation port.
The fourth entrance surface is disposed adjacent to the third entrance surface and guides light failed to pass through the third entrance surface in a direction toward a sidewall of the second lens.
The third reflection surface reflects light entering from the fourth entrance surface and guides the light to the second irradiation port.
The fourth reflection surface reflects light passed through the third entrance surface and deflected from a direction toward the second irradiation port and light reflected from the third reflection surface and deflected from the direction toward the second irradiation port, and guides the light to the second irradiation port.
In the configuration in the related art, since a light source has a certain size, it is necessary to increase the size of a reflector to a certain size or more in order to correct the influence of aberration of the optical system. Accordingly, the entire size of the vehicle lamps becomes large. When the size of the reflector is reduced, light from the light source leaks from the reflector, and thereby light flux efficiency decreases.
Hereinafter, an exemplary embodiment of the disclosure will be described with reference to the drawings.
The vehicle headlamp of the exemplary embodiment has lens modules L1 to L3 (first lens modules), lens modules L4 to L8 (second lens modules), and projection lens 107. Lens modules L1 to L3 are horizontally arranged. Lens modules L4 to L8 are horizontally arranged below lens modules L1 to L3. Light emitted from lens module L1 to L8 enters projection lens 107. Lens modules L1 to L3 and lens modules L4 to L8 are disposed to deviate from an optical axis Y of projection lens 107. Entire lens modules L1 to L3 and entire lens modules L4 to L8 are opposite to each other as shown in
Lens module L1 is configured of first lens 103a and first light source 101a which emits light toward first entrance surface 108 of first lens 103a.
Lens modules L2 and L3 have the same configuration with lens module L1. Lens module L2 is configured of first lens 103b and first light source 101b which emits light toward first entrance surface 108 of first lens 103b. Lens module L3 is configured of first lens 103c and first light source 101c which emits light toward first entrance surface 108 of first lens 103c.
Lens module L4 is configured of second lens 106a and second light source 104a which emits light toward third entrance surface 112 of second lens 106a. Lens modules L5 to L8 have the same configuration with lens module L4. Lens module L5 is configured of second lens 106b and second light source 104b which emits light toward third entrance surface 112 of second lens 106b. Lens module L6 is configured of second lens 106c and second light source 104c which emits light toward third entrance surface 112 of second lens 106c. Lens module L7 is configured of second lens 106d and second light source 104d which emits light toward third entrance surface 112 of second lens 106d. Lens module L8 is configured of second lens 106e and second light source 104e which emits light toward third entrance surface 112 of second lens 106e.
First light sources 101a to 101c are attached to base 91 as shown in
First lenses 103a to 103c are formed of a light-transmissive light guiding material.
First entrance surface 108 is formed at a center of one end of first lens 103a closer to first light source 101a. First reflection surface 110 inclined toward a side surface of first lens 103a is formed from a periphery of first entrance surface 108 to an outer circumference. Second reflection surface 111 is formed between a side opposite to first reflection surface 110 of first entrance surface 108 and a side surface of first lens 103a. First irradiation port 102 is formed at the other end of first lens 103a.
First entrance surface 108 of first lens 103a guides light from first light source 101a to first irradiation port 102. Second entrance surface 109 guides light from first light source 101a failed to pass through first entrance surface 108 to a side surface of first lens 103a. First reflection surface 110 guides light passed through second entrance surface 109 to first irradiation port 102. Second reflection surface 111 reflects light passed through first entrance surface 108 and deflected from a direction toward first irradiation port 102 and light reflected from first reflection surface 110 and deflected from the direction toward first irradiation port 102 and guides the light to first irradiation port 102. The shapes of first lenses 103b and 103c are the same as that of first lens 103a.
Lens modules L1, L2, and L3 are disposed such that light emitted from first light sources 101a to 101c is guided by first lenses 103a to 103c to overlap at a point X or a point near the point X as shown in
Second lenses 106a to 106e are formed of a light-transmissive light guiding material.
Third entrance surface 112 is formed at the center of one end of second lens 106a closer to second light source 104a. Third reflection surface 114 inclined toward a side surface of second lens 106a is formed from a periphery of third entrance surface 112 to an outer circumference. Fourth reflection surface 115 is formed between a side opposite to third reflection surface 114 of third entrance surface 112 and a side surface of second lens 106a. Second irradiation port 105 is formed on the other end of first lens 103a.
Third entrance surface 112 of second lens 106a guides light from second light source 104a to second irradiation port 105. Fourth entrance surface 113 guides light from second light source 104a failed to pass through third entrance surface 112 to a side surface of second lens 106a. Third reflection surface 114 guides light passed through fourth entrance surface 113 to second irradiation port 105. Fourth reflection surface 115 reflects light passed through third entrance surface 112 and deflected from a direction toward second irradiation port 105 and light reflected from third reflection surface 114 and deflected from the direction toward second irradiation port 105 and guides the light to second irradiation port 105. The shapes of second lenses 106b to 106e are the same as that of second lens 106a.
Lens modules L4 to L8 are disposed such that light emitted from second light sources 104a to 104e is guided by second lenses 106a to 106e to overlap at the point X or a point near the point X as shown in
Projection lens 107 has entrance surface 117 on which ray 116 passed through first lenses 103a to 103c and second lenses 106a to 106e is incident and irradiation surface 118 that emits incident ray 116. A wave-like or conical periodic structure is formed on irradiation surface 118.
Light emitted from first light sources 101a to 101c is guided by first lenses 103a to 103c and exits through projection lens 107. The light emitted from second light sources 104a to 104e is guided by second lenses 106a to 106e and exits through projection lens 107. Optical axes 205 to 207 of first lenses 103a to 103c and optical axes 309 to 313 of second lenses 106a to 106e are designed to intersect at the common point X in front of first irradiation ports 102 and second irradiation ports 105 or at a point in a vicinity thereof.
Since the focal point of projection lens 107 is set to coincide with the point X or a point in the vicinity of the point X, it is possible to emit both light exit from first light sources 101a to 101c and guided by first lenses 103a to 103c and light exit from second light sources 104a to 104e and guided by second lenses 106a to 106e as substantially parallel light.
A shape of second reflection surface 111 (sidewall) of first lenses 103a to 103c shown in
Shapes of fourth reflection surface 115, sidewalls 403 and 404 of second lenses 106a to 106e shown in
As described above, first lenses 103a to 103c and first light sources 101a to 101c are disposed in a horizontal direction with a certain interval therebetween. Furthermore, second lenses 106a to 106e and second light sources 104a to 104e are disposed in a horizontal direction with a certain interval therebetween. By superimposing the respective light distributions, the intended light distribution irradiation can be realized.
In the configuration of the present exemplary embodiment, optical axes of first lenses 103a to 103c and second lenses 106a to 106e are disposed so as to intersect each other. It is possible to perform irradiation of at least two distribution patterns of low beam irradiation and high beam irradiation without using a reflector by turning on and turning off first light sources 101a to 101c and second light sources 104a to 104e. Therefore, it is possible to realize a small and thin vehicle headlamp while forming a highly efficient irradiation light distribution.
In the above-described configuration, it is possible to prevent concentrated generation of heat by using plurality of lens modules L1 to L3 and L4 to L8 when forming a light distribution pattern. Therefore, a vehicle headlamp not requiring a special heat dissipation mechanism can be realized.
In the present exemplary embodiment, plurality of second lenses 106a to 106e and plurality of second light sources 104a to 104e are disposed in a fan shape while being shifted in angle with respect to the point X or a vicinity thereof. Accordingly, light that exits from plurality of second light sources 104a to 104e, respectively and is guided by plurality of second lenses 106a to 106e can be collected at the vicinity of the point X. Furthermore, a space at the vicinity of second light sources 104a to 104e and third entrance surface 112, fourth entrance surface 113, and third reflection surface 114 of second lenses 106a to 106e can be enlarged.
It is possible to prevent concentrated generation of heat caused by second light sources 104a to 104e by enlarging the space at the vicinity of second light sources 104a to 104e. By enlarging third entrance surface 112, fourth entrance surface 113, and third reflection surface 114 of second lenses 106a to 106e, it is possible to guide more light emitted from second light sources 104a to 104e, and to achieve high efficiency.
A certain interval is provided when disposing first lenses 103a, 103b, and 103c in the parallel direction. However, first lenses 103a, 103b, and 103c may be integrated without providing any intervals. A certain interval is provided when disposing second lenses 106a to 106e. However, second lenses 106a to 106e may be integrated without providing any intervals. In the present exemplary embodiment, second lenses 106a to 106e and second light sources 104a to 104e are disposed at the same distance from the vicinity of the point X. However, second lenses 106a to 106e and second light sources 104a to 104e may not be disposed at the same distance. First lenses 103a, 103b, and 103c and first light sources 101a, 101b, and 101c may not be disposed at the same distance.
Plurality of second lenses 106a to 106e, plurality of second light sources 104a to 104e, and plurality of optical axes 309 to 313 created by the second lenses and the second light sources are disposed in a fan shape with the point X or the vicinity thereof as the center while being shifted in angle. Here, the shifted angles may be the same angle or may be different angles. This also applies to first lenses 103a, 103b, and 103c, first light sources 101a, 101b, and 101c, and plurality of optical axes 205 to 207 created by the first lenses and the first light sources.
The material of the lens may be inorganic glass or an organic plastic represented by acrylic or polycarbonate. It is possible to realize a lens configuration that enables thinning without using a reflector with this arrangement. Therefore, the problem of the vehicle headlamp that the size increases and the efficiency is lowered is solved.
The light distribution of the vehicle headlamp will be described with reference to
When a front vehicle such as an oncoming vehicle or a foregoing vehicle appears while traveling with irradiation light distribution pattern 1 of
Since there are many oncoming vehicles when traveling in the city, the irradiation time of the low-beam light distribution pattern formed by irradiation of first light sources 101a to 101c is longer than that of the high-beam light distribution pattern formed by irradiation of second light sources 104a to 104e.
That is, the heat generated when first light sources 101a to 101c emit light increases. In the present exemplary embodiment, first lenses 103a to 103c are designed to be longer than second lenses 106a to 106e, and the lenses themselves take the place of the heat dissipation mechanism. Therefore, it has a configuration capable of dissipating heat generated when first light sources 101a to 101c emit light.
In the above-described exemplary embodiment, three lens modules L1 to L3 of first light sources 101a to 101c and first lenses 103a to 103c and five lens modules L4 to L8 of second light sources 104a to 104e and second lenses 106a to 106e are used, but they may not be three or five.
According to the configuration of the present exemplary embodiment, the first lenses and the second lenses are disposed so as to be shifted from the optical axis of the projection lens and to be opposite to each other, and the light emitted from the first lenses and the second lenses is emitted through the projection lens. Therefore, the pattern of the light distribution can be switched by switching lighting of the first light sources and the second light sources.
The vehicle headlamp in the related art illuminates with a light distribution pattern using a reflector. However, since the vehicle headlamp of the present exemplary embodiment does not use the reflector, it can be made thinner than the vehicle headlamp in the related art. That is, the vehicle headlamp of the present exemplary embodiment can be made small and thin while the light flux forms irradiation light distribution with high efficiency.
The present disclosure is to provide a small and thin lighting fixture capable of switching projected light distributions with high efficiency and can be applied to not only vehicles but also to the use of lighting fixtures for other vehicles and buildings.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2017-247127 | Dec 2017 | JP | national |
